Dyeing wool fast black.



UNITED. STATES PATENT FFICE.

PAUL JULIUS AND RICHARD LAIBLIN, LUDWIGrSHABEN, GERMANY, AS- SIGNORS TO THE BADISOHE ANILIN AND SODA FABRIK, OF SAME PLACE.

DYVEING wool. FAST BLACK.

SPECIFICATION forming' part of Letters Patent No. 634,824, dated October 10, 1899.

Application filed April 24, 1899. Serial No. 714,299. (No specimens.)

To all whom it may concern:

vBe it known that we, PAUL JULIUS, a subject of the EmperorofAustria-Huugary, and RICHARD LAIBLIN, a subject of the King of \Viirtemburg, both doctors of philosophy, residing at Ludwigshafen-on-the-Rhiue, in the Kingdom of Bavaria and Empire of Germany, have invented new and useful Improvements in the Production of Fast-Black Shades on Wool, (for which applications for patent were filed in Germany, No. 23,640, dated October 31, 1898; in England, No. 6,244, dated March 22, 1899, and in France, No. 275,117, dated March 25, 1899,) of which the following is a specification. I

Our invention relates to the production of beautiful black shades on woolen goods which possess a valuable degree of fastness by the aid of the disazo dyes which are obtained from ortho-amido-pheuol-para-sulfoacid. Some of these secondary disazo dyes have long been known andhave been patented under the EnglishLetters Patent No. 10,845, of 1888; but when dyed in the usual way they yield shades which are not beautiful and vary from violet to foxy black. They have not been adopted in the dyeing industry, and the rights under the said Letters Patent have been allowed to lapse. We have discovered that these dyes can be used for the production of valuable fast deep-black colorations on wool. The valuable shades are obtained by dyeing wool in the ordinary way with the coloring-matters and treating the dyed fabric with a chromate or a chrome salt. The fabric assumes a deepblaek color and has a beautifully blueish, greenish, or blue-violet cast upon looking over the goods, and the shades are of extraordin ary fastness. Further, the intensity of the color is considerably increased. The shades produced are fast to alkali and acid. The fastness to washing and fulliug is good,. andiu point of fastness to light the shades so obtained are very excellent. 1

The disazo coloring-matters thatare used are those obtained from ortho-amido-phenol para-sulfo-acid with alpha-naphthylamin as middle component and a naphthol or dioxy naphthalen e-or sulfo-acids thereof as end com ponents.

The following example will serve to illustrate the manner in which our invention can best be carried into practical effect: Take, say, thirty (30) kilograms of merino cloth and dye this in a bath composed ofnine hundred (900) liters of water, one and a half (1%) kilo grains of calcined Glauber salt, and one (1) kilogram of the coloring-matter from ortho amido-phenol-para-sulfo-acid, alpha-naphthylamin, and betauaphthol-Ssulfo-acid. Dye first by boiling the goods for a quarter of an hourin this bath while neutral. Then add two (2) kilos of sodium bisulfate, which can, if desired, be replaced partly or wholly by acetic or other acids. The sodium bisulfate (or its substitute) is preferably added in four (4.) portions at intervals of about a quarter of an hour. When the bath is exhausted, add to it about six hundred (600) grams of potassium b'ichromate and boil the goods in the solution so obtained for half an hour. Swill the goods and work up in the usual way. The treatment with bichromate can be effected in a separate bath, if desired. The manner of dyeing remains the same if instead of the coloring-matter stated in the example the other disazo dyes herein defined be taken.

The above example describes a good way of Working in practice according to which it' is possible to readily obtain a certain definite shade; but the manner of proceeding may be varied without departure from our invention. Thus the chromium compound used may be added to the dye-bath at. the start or when the dyeing has been partly effected. Further, the dye-baths after the removal of the goods contain some ofthe chromium com-' pound. This can be utilized by adding a fresh proportion of dye and dyeing another batch of goods from the same liquid, adding during the operations the further requisite quantity of chromium compound, and so on.

The following table indicates the shade obtained with the coloring-matters containing the components mentioned as end components:

End component. Shade obtained.

Alpha-naphthol-4-sulfoacid Deep black. R-salt "l Blue-black. Alpha-naphthol-4-sulfoacid 5 Do.

1 .1-dioxynaphthalene-4-sulfoacid Gleenish black.

Now what We claim is The process for the production of fast-black shades on wool by dyeing the woolen goods from an acid-bath with the hereindeseribed secondary disazo dyes from ortho-amido-phenol-para-snlfo-acid and treating the dyeings with a chrome salt, all substantially as hereinbefore described.

In testimony whereof We have hereunto set our hands in the presence of two subscribing witnesses.

PAUL JULIUS. RICHARD LAIBLIN.

WVit-nesses:

ERNEST F. EHRHARDT, J. L. HEINKE. 

